White 1 does the trick. 3 is one line longer than a monkey jump, but
it cannot be cut off. If White tries playing at 3 first, then Black
plays A, and 1 no longer works, since White runs out of liberties.

BGJ did not include the problem diagram on the solution
page, it is included here for easy reference.

The centre white group can clearly live or be killed by putting a
stone in the middle of its eyespace.

The white group on the left can be killed as shown here.

The black group, which has no eyes, is unconditionally alive - it is a
rare animal known as the double headed dragon. (Think how White might
put it into atari.)

This position arose in a game in which the white stones were held by
Allan Scarff's computer program, Microgo. The program understands false
eyes very well, but thought it had killed all Black's stones.

This article is from the
British Go Journal
Issue 64
which is one of a series of back issues now available on the web.